题目

（题文）There is only one cake, so we have to _______.You have a half and I have a half.A. wait B. share C. move D. cook 答案：【答案】B【解析】句意：只有一块蛋糕，所以我们必须得分享，你一半我一半。wait等待；share分享；move移动；cook做饭。根据句意You have a half and I have a half可知，这一块蛋糕需要两个人共同分享，故应选B。在梯形面积公式S=12(a+b)h中，若S=10，b=3，h=4，则a= ．